Organic fluorine compounds



Patented Mar. 17, 1936 UNITED STATES PATENT OFFICE ORGANIC FLUORINECOMPOUNDS poration of Delaware No Drawing. Application January 12, 1933,Serial No. 651,352

. 7 Claims. (01. 260 -44) This invention relates to the manufacture ofnew chemical compounds useful as intermediates in the production of newdyestuffs and other products of a useful nature.

Amino-arylthiazoles are well known compounds which are useful in themanufacture of dyestuffs and for other purposes. a

An object of the present invention is to provide new substitutedamino-benzothiazoles and more particularly amino-benzothiazole having afluorine atom substituted for a hydrogen of the benzene nucleus. Furtherobjects are to provide new compositions of matter and to advance theart. Other objects will appear hereinafter.

These objects are accomplished according to our invention by reacting,in a suitable solvent or suspending medium, para-fiuoro-phenyl-thioureaswith sulfuryl chloride, bromine, chlorine, mixtures of halogens withsulfuryl chloride, sulfur chloride or other'compounds which wouldliberate bromine or chlorine or mixtures thereof, whereby,l-amino-5-fluoro-benzothiazoles are obtained. Other known methods ofclosing the ring may be employed.

The 1-amino-5-fluoro-benzothiazoles may be represented by the formula inwhich B may represent hydrogen, alkyl or a substituted or unsubstitutedaryl nucleus. Among the compounds which we have found to be particularlyvaluable are the following: 1-amino-5-fiuoro-benzothiazole 1 (phenyl)amino-5-fiuoro-benzothiazole These compounds may be prepared by reactingthe appropriate fluoro-phenyl thiourea with sulfuryl chloride or thelike, for example, the two compounds specifically mentioned above may beprepared respectively from the following thioureas:

p-fluoro-phenyl thiourea phenyl -p-fluoro-phenylthiourea i ii H t H ESEF wherein R represents the desired alkyl, aryl or aralkyl radical. WhenR. in the above formula represents an aryl group, the product formed bytreating with sulfuryl chloride will generally be a thiazole having boththe nitrogen and sulfur atoms connected to the benzene nucleuscontaining the fluorine atom with some amounts of the compound formedwith the nitrogen and sulfur connected to the otherv aryl nucleus.

The fluoro-phenyl thioureas may be prepared by reacting a fluorinatedamine of the benzene series such as, for example, para-fiuoro-anilinewith a suitable thiocyanate such as, for instance, an alkali metalthiocyanate or with an alkyl-isothiocyanate, an aryl-iso-thiocyanate orcarbon disulfide. The thioureas may be of the symmetrical orunsymmetrical type, for instance, parafiuoro-phenyl-thiourea beingunsymmetrical and parazpara difiuoro diphenyl thiourea beingsymmetrical. Any of the thioureas thus prepared may be treated inaccordance with the process of the present invention. Among suchcompounds may be mentioned as additional examples those of the generalformula rte- H A H F in which R represents methyl, ethyl, butyl,naphthyl or an aromatic radical of the benzene series containing alkyl,alkoxy and halogen substituents. The production of compounds of thistype is disclosed in our co-pending application Serial No. 630,248 filedAugust 26, 1932.

In order to more clearly illustrate a method for preparing the newcompounds of our invention the following example is given:

Example 34 grams of p-fiuoro-phenyl-thiourea were mixed with 120 cc. ofchlorobenzene. To this mixture was slowly added, from a dropping funnel,the following mixture:

15 cc. sulfuryl chloride 2.6 cc. bromine cc. chlorobenzene Vigorousstirring was maintained during this addition and large volumes ofhydrohalide gas were given off. When the reaction was complete, theproduct was filtered off and dissolved in water. The water solution wasthen treated with bone black, filtered, cooled, and the free baseprecipitated by adding ammonia. The yield of the crude hydrohalide was31 grams. The yield of the free base was over 16 grams. The l-amino-5-fluoro-benzothiazole melted between 181 and 182 C.

The other thiazoles of our invention may be prepared according to thesame method. Other methods for preparing our new compounds will bereadily apparent to those skilled in the art.

While we have disclosed certain specific members of our new class ofcompounds, many other compounds falling within the class will be readilyapparent to those skilled in the art without departing from the spiritof our invention. Accordingly, the scope of our invention is to belimited solely by the appended claims construed as broadly as ispermissible in view of the prior art.

We claim:

1. The 1-amino-5-fluoro-benzothiazole.

2. The compound l-(phenyl)-amino-5-fiuorobenzothiazole.

3. A new class of compounds represented by the formula:

N H R/ 0l IR wherein R represents a benzene nucleus having a fluorineatom substituted for hydrogen in the position para to the nitrogen atom,and R1 represents hydrogen or a hydrocarbon radical.

4. A new class of compounds represented by the formula:

N\ 1 1 R \ONR1 wherein R represents a benzene nucleus having a fluorineatom substituted for hydrogen in the position para to the nitrogen atom,and R1 represents a hydrocarbon radical.

5. A new class of compounds represented by the formula:

N\ H R/ CI IR| wherein R represents a benzene nucleus having a fluorineatom substituted for hydrogen in the position para to the nitrogen atom,and R1 represents an aromatic hydrocarbon radical of the benzene ornaphthalene series.

6. A new class of compounds represented by the formula:

N\ 11 R/ Cl IR wherein R represents a benzene nucleus having a fluorineatom substituted for hydrogen in the position para to the nitrogen atom,and R1 represents an aromatic hydrocarbon radical of the benzene series.

'7. A class of compounds represented by the general formula

